This is what I understand so far, please correct me if I am wrong:
Let’s say a stock short sell interest rate today in IB is 5%, IB calculates the short sell interest daily, the short sell interest for today would be 5%/365
Then tomorrow the interest rate goes up to 10%. The tomorrow interest cost becomes 10%/365
and this is true if I didn’t close the short sell and hold for 2 days.
Another issue is if the stock is $0.1, IB actually counts it as $1, the whole number of it, to calculate…